Experimental Study On Mechanical Properties Of New Formworks

With the rapid development of the construction industry,the traditional building formwork gradually cannot meet the requirements of green construction and sustainable development.The development of new materials and new structural forms of formwork has become the main research direction.Aluminum alloy formwork,steel frame and aluminum frame plastic formwork as a new formwork system are gradually favored by the formwork industry with their unique advantages.With the advantages of light weight,high turnover rate and high recycling rate,aluminum alloy formwork,steel framework and aluminum frame plastic formworkdevelops rapidly in the formwork industry.However,the two kinds of templates started late in China,and the mechanical properties of them are not clear.The research of aluminum alloy template is not perfect,and various specifications have not been formulated.It is of great significance to study the mechanical properties of aluminum alloy template and the influencing factors of the rigidity of aluminum alloy template.The steel frame and aluminum frame plastic formwork are still in the stage of R & D and trial use,and have not formed mature formwork design theory.At the same time,there is a lack of in-depth understanding of the mechanical properties of the formwork.It is necessary to study the mechanical properties and structural optimization analysis of the steel frame and aluminum frame plastic formwork,so as to provide basis for the design,promotion and application of the formwork later.The main contents of this paper are as follows:(1)through the material property test of steel,aluminum alloy and plastic,the constitutive relationship and relevant mechanical property indexes of the three materials are determined.(2)the static test of aluminum alloy formwork is carried out to explore the influence of different back rib spacing,width and transverse rib on the rigidity of formwork,and the deflection and Load displacement curve;(3)through the rigidity test and bearing capacity test of steel frame and aluminum frame plastic formwork,the deflection,ultimate bearing capacity and failure modes of the two formworks under the given load are obtained respectively.Test results of aluminum alloy formwork: the larger the load,the greater the distance between back ribs,the wider the formwork,the larger the deformation of the formwork;the greater the influence of transverse ribs on the rigidity of the formwork,the smaller the impact on the bearing capacity;refer to the R-O model,fit the load displacement curve obtained from the test,get the fitting parameter equation,and explore the change rule of parameters.The test results of steel frame and aluminum frame plastic formwork show that: the formwork size and support spacing have great influence on the formwork rigidity;the ability of steel frame plastic formwork to resist deformation is stronger than aluminum frame plastic formwork,GS2400 × 400 is recommended as the standard formwork for steel frame plastic formwork,GS2400 × 400 is recommended as the standard formwork for aluminum frame plastic formwork.